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Date: Sun, 8 Nov 2009 11:30:38 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
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Subject: Re: 1.7] BUG - GREP slows to a crawl with large number of matches   	on  	a single file
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On Nov  7 15:26, aputerguy wrote:
> 
> Changing LC_ALL also solved the problem for me.
> But it begs the question of how many other basic and take-for-granted
> functions might be affected by this apparent UTF-8 slowdown. And again we,
> are not talking about some minor overhead, we are talking about a slowdown
> of 1500X or 150,000%!!!!

Yeah, that's really still strange to me.  In my testing, the multibyte
to widechar conversion performed by grep in case of UTF-8 took only
1.5 up to 4 seconds for 10 times the number of input lines as in your
case.  It still puzzles me where the time is wasted in grep.


Corinna

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Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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